β-oxidation Defect

By | June 10, 2022

A β-oxidation defect or fatty acid oxidation defect is a frequently occurring and congenital metabolic disorder in Central Europe. If the β-oxidation is disturbed, not enough energy is produced. With increased glucose consumption and the associated drop in blood sugar levels, ketone body synthesis is also reduced. In addition to symptoms such as muscle weakness and cardiac arrhythmia, the resulting energy deficit also results in an insufficient supply to the brain. If left untreated, this can lead to brain damage or, in the worst case, death.

What is a β-oxidation defect?

In order for organisms to live, they must absorb energy and process it in the body. Carbohydrates, fats and proteins are metabolized in different ways. The energy-rich dietary fats are first broken down in the digestive tract and transported via the blood to the body cells and stored there. For what is the definition of hyperemia, please visit healthknowing.com.

The body uses these depots primarily when energy can no longer be provided from carbohydrates, for example during periods of hunger or when there is an increased need for energy. So that the energy can be released and used, the free fatty acids are transported via transporters (e.g. L-carnitine) into the power plants of the cells, the mitochondria. The multi-stage degradation process is called β-oxidation.

The fatty acids are gradually broken down here with the help of different enzymes and finally introduced into the citric acid cycle in order to provide the body with ATP, the universal and immediately available energy carrier, as the end result. Depending on the type of fatty acid (medium- or long-chain), different enzymes are responsible for the oxidation.

If there is now a deficiency of this special enzyme in the body, the breakdown of the fatty acid is disturbed – a β-oxidation defect occurs . The intermediate metabolic products remain in the cells, cannot be further processed or transported away and thus quickly develop a toxic effect on the brain, muscles and liver.


These metabolic disorders are caused by either congenital enzyme or transporter defects or a so-called secondary carnitine deficiency. This deficiency can in turn be caused by primary diseases (disorders in the metabolism of amino acids), or can also occur with certain forms of treatment for epilepsy, manifest itself in the context of dialysis or develop as a result of persistent malnutrition.

Symptoms, Ailments & Signs

Depending on the enzyme defect, different symptoms appear. These are triggered by a metabolic crisis due to a lack of energy supply. Fat metabolism usually supplies up to 80 percent of the total metabolic energy. Cardiac and skeletal muscle in particular depend on the provision of energy from fatty acid oxidation.

If there is a defect here, more glucose is broken down instead, which can lead to massive hypoglycaemia and even coma after about twelve hours in this state. The symptoms often appear in the first few months of life. In addition to an enlarged liver and periodic low blood pressure, affected infants also show abnormalities in heart activity up to and including heart and organ failure.

If left untreated, there is a high risk of mortality. Hypoglycaemia and liver diseases can be observed in forms that occur later in childhood and adolescence. Patients with the late-onset form suffer from widespread muscle pain and cramps and periodic renal failure.

Often there is also a pronounced stress intolerance. In the case of disturbed beta-oxidation of long-chain fatty acids, the lack of omega-3 fatty acids leads to reduced development of visual and cognitive functions.

Diagnosis & course of disease

Tandem mass spectrometry has become firmly established in newborn screening for the diagnosis of metabolic defects and, as a non-invasive diagnostic method, also represents the current examination standard. Here, the enzyme activity in blood serum, skin cells, muscle tissue or even in the affected gene itself is determined. If the symptoms only appear in childhood or adolescence, the diagnosis is often complicated by the fact that the patients were previously clinically completely normal.

However, since a metabolic crisis develops into a coma if left untreated, there is a high risk of death if the cause is not identified. On the other hand, if the disease is detected early, most cases of the disease can be treated very well. The exception here are a few severe cases in which life expectancy is comparatively lower due to a permanent disease of the heart muscle.

When should you go to the doctor?

The person affected by this disease is dependent on a visit to a doctor. As a rule, it cannot heal on its own, so that treatment by a doctor is necessary in any case.

The earlier a doctor is consulted for the β-oxidation defect, the better the further course of this disease is, so that a doctor should be contacted as soon as the first symptoms and complaints appear. A doctor should be contacted if the person concerned suffers from very severe heart problems.

In most cases, the disease causes people to repeatedly lose consciousness and suffer from low blood pressure. In particular, strenuous or stressful activities and activities can lead to a loss of consciousness or even a coma and should therefore always be examined by a doctor.

Even severe pain in the muscles often indicates a β-oxidation defect if it occurs over a longer period of time and does not go away on its own. As a rule, the disease can be easily diagnosed by a general practitioner.

Treatment & Therapy

In the case of acute metabolic crises, immediate medical treatment is absolutely necessary. Treatment is by infusion with glucose, and in children with primary carnitine deficiency also with high-dose L-carnitine. In severe cases, a continuous supply of high-dose carbohydrates via a gastric tube is also possible.


Since the disease is congenital, there are no preventive measures. However, a targeted diet can make a significant contribution to avoiding metabolic crises and thus hypoglycaemia and preventing a fasting-induced coma. For this purpose, a regular carbohydrate-rich diet should be ensured.

The proportion of carbohydrates should be between 55 to 60 percent of the energy intake, depending on the form of the oxidation disorder with 20 to 25 percent fat. Rice flakes are recommended for older babies and boiled cornstarch as a food additive for small children. Long periods of fasting, so-called hunger phases, should be avoided and should not last longer than ten to twelve hours in young people.

If there is a deficit in omega-3 fatty acids, which affects the development of visual and cognitive functions, substitution with fish oil preparations is recommended. In general, if you notice the first signs of hypoglycaemia in yourself or others, it is advisable to give yourself sugary food, preferably dextrose or sweet drinks. However, foods that contain a lot of fat should be avoided. If in doubt, a doctor should be consulted.

You can do that yourself

Patients with this disease must first be evaluated to determine whether the underlying β-oxidation defect is a disease that can be treated. In most cases, however, the metabolic disorder is congenital and can become a major burden, since deficiency situations lead to metabolic crises and can be fatal.

It is therefore important to avoid any hypoglycaemia. When eating, patients should ensure that they eat foods that are very rich in carbohydrates, such as bread, pasta, potatoes, rice, rice flakes, corn starch, fruit, glucose, sweet drinks, etc. In addition, patients should eat very regularly. In order to avoid a fasting state, carbohydrate-rich meals should be eaten every few hours. How high the fat content of the diet should be at the same time is determined by the doctor treating you, depending on the severity of the β-oxidation defect.

The doctor may also recommend that patients with a lack of omega-3 fatty acids replace them. There are now quite inexpensive fish oil capsules on the market. A β-oxidation defect is not a very common disease, so no special self-help groups have formed here. However, there is the Association for Association for Congenital Metabolic Disorders (VfASS) in Berlin (www.vfass.de), through which members can exchange information and get information. Such an exchange has proven to be helpful for those affected, especially in the case of such rare and at the same time life-threatening diseases such as the β-oxidation defect.

β-oxidation Defect